Ryan Camacho is facing charges of first-degree murder and first-degree burglary.
Authorities say Camacho, a repeat offender, broke into Welsh's home inside the beltline near Wade Avenue and St. Mary's Street in January and killed her.
She was on the phone with 911 when she was attacked.
Welsh was a biology teacher at the Ravenscroft School.
The school is having a celebration of life for the beloved teacher on March 29.
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